There are many applications in academic, industrial, and medical fields that benefit from devices and methods that are capable of accurately and controllably delivering fluids, such as liquids and gases, that have a beneficial effect when administered in known and controlled quantities. Such devices and methods can be particularly useful in the medical field where treatments for many patients include the administration of a known amount of a substance at predetermined intervals.
Infusion pumps have been developed for the administration of insulin and/or other medicaments for those suffering from both type I and type II diabetes. Some pumps configured as portable infusion devices can provide continuous subcutaneous insulin injection and/or infusion therapy for the treatment of diabetes. Such therapy may include the regular and/or continuous injection or infusion of insulin into the skin of a person suffering from diabetes and offer an alternative to multiple daily injections of insulin by an insulin syringe or an insulin pen. Such pumps can be ambulatory/portable infusion pumps that are worn by the user and may use replaceable cartridges. Examples of such pumps and various features that can be associated with such pumps include those disclosed in U.S. patent application Ser. No. 13/557,163, U.S. patent application Ser. No. 12/714,299, U.S. patent application Ser. No. 12/538,018, U.S. patent application Ser. No. 13/838,617, U.S. patent application Ser. No. 13/827,707 and U.S. Pat. No. 8,287,495, each of which is incorporated herein by reference.
Portable infusion pumps can deliver medicament to patients through infusion sets that include tubing extending from the pump and a cannula with an associated needle that penetrates the patient's skin at an infusion site to allow infusion of the medicament through the cannula and into the patient. If a patient leaves the needle injected at the injection site for too long a period of time, negative side effects such as infection, scarring and lumps due to build up of fatty tissue can result. Therefore, patients are often instructed to rotate injection sites to avoid or minimize side effects. Depending on the type of cannula used, the general physiological response of the patient, and other factors, the time between insulin site rotations can vary. Often, sites are rotated every 24-48 hours or every 48-72 hours. In addition, when the needle is first inserted at a particular site, the body has a natural inflammatory response. This inflammatory response can affect the body's absorption of insulin or other medicaments at the site.